In the source of a connector: Active Directory or text file, a data change occurs, e.g. the name or phone number is changed for a user. Yet this change is not applied to the user in the XPhone Server even though the connector has already run.
A connector only modifies users on the XPhone Server that were created by the connector. If a user was created manually, the user's data is never changed by a connector.
In the XPhone Server administration interface, in the properties of the respective user in the upper right corner you can see a "Managed by: XY connector". If you do not find this information for the user, then they were created manually.
You must delete the user so it is created by the connector. Note, however, that deleting a user deletes all this user's voicemail greetings, also the assignment to teams or workgroups as well as the server-based call journal and all as undelivered faxes, voicemails and, where applicable, text messages.
If a telephone number that has been changed for a user is not accepted, check in the connector settings whether the option "Once on creation of a user" has been set for the line allocation. This option determines that phone numbers are only defined when a new user is created, but not changed again later.